Add support for Rosstech Digital Control Unit DCU-706/Sundance/Jacuzzi (

#2612)

README.md

@@ -350,6 +350,7 @@ See [CONTRIBUTING.md](./docs/CONTRIBUTING.md).
     [262]  Fine Offset Electronics WH46 air quality sensor
     [263]  Vevor Wireless Weather Station 7-in-1
     [264]  Arexx Multilogger IP-HA90, IP-TH78EXT, TSN-70E
+    [265]  Rosstech Digital Control Unit DCU-706/Sundance/Jacuzzi
 
 * Disabled by default, use -R n or a conf file to enable
 

conf/rtl_433.example.conf

@@ -491,6 +491,7 @@ convert si
   protocol 262 # Fine Offset Electronics WH46 air quality sensor
   protocol 263 # Vevor Wireless Weather Station 7-in-1
   protocol 264 # Arexx Multilogger IP-HA90, IP-TH78EXT, TSN-70E
+  protocol 265 # Rosstech Digital Control Unit DCU-706/Sundance/Jacuzzi
 
 ## Flex devices (command line option "-X")
 

include/rtl_433_devices.h

@@ -272,6 +272,7 @@
     DECL(fineoffset_wh46) \
     DECL(vevor_7in1) \
     DECL(arexx_ml) \
+    DECL(rosstech_dcu706) \
 
     /* Add new decoders here. */
 

src/CMakeLists.txt

@@ -204,6 +204,7 @@ add_library(r_433 STATIC
     devices/revolt_nc5462.c
     devices/rftech.c
     devices/rojaflex.c
+    devices/rosstech_dcu706.c
     devices/rubicson.c
     devices/rubicson_48659.c
     devices/rubicson_pool_48942.c

src/devices/rosstech_dcu706.c

@@ -0,0 +1,139 @@
+/** @file
+    Rosstech Digital Control Unit DCU-706/Sundance.
+
+    Copyright (C) 2023 suaveolent
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+*/
+
+#include "decoder.h"
+
+/** @fn int rosstech_dcu706_decode(r_device *decoder, bitbuffer_t *bitbuffer)
+Rosstech Digital Control Unit DCU-706/Sundance/Jacuzzi.
+
+Supported Models:
+Sundance DCU-6560-131, SD-880 Series, PN 6560-131
+Jacuzzi DCU-2560-131, Jac-J300/J400 and SD-780 series, PN 6560-132/2560-131
+
+Data layout:
+
+    SS IIII TT CC
+
+- S: 8 bit sync byte and type of transmission
+- I: 16 bit ID
+- T: 8 bit temp packet in degrees F
+- C: 8 bit Checksum: Count 1s for each bit of each element:
+                     Set bit to 1 if number is even 0 if odd
+
+11 bits/byte: 1 start bit, 0 stop bits and odd parity
+
+*/
+
+static uint8_t calculateChecksum(const uint8_t *data, size_t size)
+{
+    uint8_t checksum = 0;
+
+    for (int bit = 0; bit < 8; bit++) {
+        int count = 0;
+
+        for (size_t i = 0; i < size; i++) {
+            count += (data[i] >> bit) & 1;
+        }
+
+        if (count % 2 == 0) {
+            checksum |= (1 << bit);
+        }
+    }
+
+    return checksum;
+}
+
+static int rosstech_dcu706_decode(r_device *decoder, bitbuffer_t *bitbuffer)
+{
+    uint8_t const preamble_data_transmission[] = {0xDD, 0x40};
+    // The Bond command also contains the temperature
+    uint8_t const preamble_Bond[] = {0xCD, 0x00};
+    int const preamble_length = 11;
+
+    // We need 55 bits
+    uint8_t msg[7];
+
+    if (bitbuffer->num_rows != 1
+            || bitbuffer->bits_per_row[0] < 55
+            || bitbuffer->bits_per_row[0] > 300) {
+        decoder_logf(decoder, 2, __func__, "bit_per_row %u out of range", bitbuffer->bits_per_row[0]);
+        return DECODE_ABORT_EARLY; // Unrecognized data
+    }
+
+    unsigned start_pos = bitbuffer_search(bitbuffer, 0, 0, preamble_data_transmission, preamble_length);
+
+    if (start_pos == bitbuffer->bits_per_row[0]) {
+
+        start_pos = bitbuffer_search(bitbuffer, 0, 0, preamble_Bond, preamble_length);
+
+        if (start_pos == bitbuffer->bits_per_row[0]) {
+            return DECODE_ABORT_LENGTH;
+        }
+    }
+
+    if (start_pos + 55 > bitbuffer->bits_per_row[0]) {
+        return DECODE_ABORT_LENGTH;
+    }
+
+    bitbuffer_extract_bytes(bitbuffer, 0, start_pos, msg, sizeof(msg) * 8);
+
+    uint8_t msg_type = (msg[0] << 1) | (msg[1] >> 7); // S
+    uint8_t id_high  = (msg[1] << 4) | (msg[2] >> 4);
+    uint8_t id_low   = (msg[2] << 7) | (msg[3] >> 1);
+    uint16_t id      = (id_high << 8) | id_low;       // I
+    uint8_t temp_f   = (msg[4] << 2) | (msg[5] >> 6); // T
+    uint8_t checksum = (msg[5] << 5) | (msg[6] >> 3); // C
+
+    // Create a uint8_t array to hold the extracted values
+    uint8_t extracted_data[4];
+    extracted_data[0] = msg_type;
+    extracted_data[1] = id_high;
+    extracted_data[2] = id_low;
+    extracted_data[3] = temp_f;
+
+    uint8_t calculated_checksum = calculateChecksum(extracted_data, sizeof(extracted_data) / sizeof(extracted_data[0]));
+    if (calculated_checksum != checksum) {
+        decoder_logf(decoder, 2, __func__, "Checksum failed. Expected: %02x, Calculated: %02x.", checksum, calculated_checksum);
+        return DECODE_FAIL_MIC;
+    }
+
+    /* clang-format off */
+    data_t *data = data_make(
+        "model",            "Model",              DATA_STRING,   "Rosstech-Spa",
+        "id",               "ID",                 DATA_FORMAT,   "%04x",    DATA_INT,   id,
+        "msg_type",         "Transmission Type",  DATA_STRING,   msg_type == 0xba ? "Data" : "Bond",
+        "temperature_F",    "Temperature",        DATA_FORMAT,   "%d F",    DATA_INT,   temp_f,
+        "mic",              "Integrity",          DATA_STRING,   "CHECKSUM",
+        NULL);
+    /* clang-format on */
+
+    decoder_output_data(decoder, data);
+    return 1;
+}
+
+static char const *const output_fields[] = {
+        "model",
+        "id",
+        "msg_type",
+        "temperature_F",
+        "mic",
+        NULL,
+};
+
+r_device const rosstech_dcu706 = {
+        .name        = "Rosstech Digital Control Unit DCU-706/Sundance/Jacuzzi",
+        .modulation  = OOK_PULSE_PCM,
+        .short_width = 200,
+        .long_width  = 200,
+        .reset_limit = 2000,
+        .decode_fn   = &rosstech_dcu706_decode,
+        .fields      = output_fields,
+};